LONDON — Russia’s energy giant is threatening to send less gas to Europe — but Germany, one of its main importers, has rejected the idea.

Majority state-owned Gazprom said Monday that due to unforeseeable circumstances it is not in a position to comply with gas contracts in Europe.

Germany’s energy firm, Uniper, confirmed to CNBC that Gazprom had claimed “force majeure” on its supplies. Force majeure, a legal term, occurs when unforeseeable circumstances prevent one party from fulfilling its contractual duties, in theory absolving them from penalties.

“It is true that we have received a letter from Gazprom Export in which the company claims force majeure retroactively for past and current shortfalls in gas deliveries. We consider this as unjustified and have formally rejected the force majeure claim,” Lucas Wintgens, spokesperson for Uniper, told CNBC’s Annette Weisbach.

RWE, another German energy company, confirmed to CNBC that it had also received a force majeure notice from Gazprom.

Gazprom was not immediately available for comment when contacted by CNBC Tuesday.

Officials in Germany and elsewhere in Europe have become increasingly concerned about the possibility of a complete shutdown in gas supplies from Russia. These fears intensified after Nord Stream 1 — a key gas pipeline from Russia to Germany — was closed earlier this month for maintenance work, with some doubting that flows will be fully restored after works are concluded on July 21.